Device for producing a light spot in a microscope

Abstract

A microscope is provided with a supplementary means for producing a light spot in the object plane of the microscope objective lens. The supplementary means comprises a light source from which a collimated light beam is derived, a focusing lens receiving the collimated beam and a coupling lens disposed between the first lens and the objective lens. The supplementary means has the following features: the focal point of the focusing lens is in the plane of the image of a specimen in the object plane as obtained through the objective lens and the coupling lens, the light beam fills the clear aperture of the objective lens without substantial light loss and the light source and the focusing lens may be moved together to displace the light spot within or away from the object plane of the objective lens.

We claim: 
     
       1. A microscope provided with supplementary means for producing a light spot in the object plane of the microscope objective lens said means comprising   a focusing lens receiving said collimated beam, said focusing lens having a focal point; and   a coupling lens disposed between said focusing lens and said objective lens whereby said light spot is produced from said collimated beam in said object plane of said objective lens;   said means further characterized in that   said focal point of said focusing lens is in the plane of the image of a specimen in said object plane as obtained through said objective lens and said coupling lens;   said light beam fills the clear aperture of said objective lens without substantial light loss;   said focusing lens is movable together with said light source in a plane perpendicular to the axis of said lens whereby said light spot is displaced in said object plane of said objective lens; and   the central ray of light from said light source passes through the center of said clear aperture of said objective lens.   
     
     
       2. A microscope as defined in claim 1, characterised in that said focusing lens and said light source are movable together parallel to said axis. 
     
     
       3. A microsocpe as defined in any one of the claims 1 or 2, characterized in that said center of said clear aperture of said microsocpe objective lens coincides with the rear focal point of said coupling lens. 
     
     
       4. A microscope as defined in claim 1, characterised in that said light source is a laser source;   a light-splitting mirror characterised by wavelength-dependent reflectance is disposed between said coupling lens and said objective lens; and   the light from said laser source and the visible light from said specimen in said object plane have a common path between said mirror and said objective lens and the majority of one of said lights is transmitted by said mirror while the majority of said other light is reflected by said mirror.